Electronic article surveillance (“EAS”) systems are commonly used in retail stores and other settings to prevent the unauthorized removal of goods from a protected area. Typically, a detection system is configured at an exit from the protected area, which comprises one or more transmitters and antennas (“pedestals”) capable of generating an electromagnetic field across the exit, known as the “interrogation zone.” Articles to be protected are tagged with an EAS marker that, when active, generates a response signal when passed through this interrogation zone. An antenna and receiver in the same or another “pedestal” detects this response signal and generates an alarm. Certain EAS tags, commonly known as “alarming” tags, include a processor and audible alarm transducer within the actual tag device. Thus, the actual tag “knows” when it has been interrogated by an EAS portal and emits an audible alert when triggered.
Irrespective of the specific type of EAS tag in use, EAS tags often include a power supply, such as a battery, that powers the internal components of the tag for use. Indeed, tags often include a battery or similar power supply that is permanently fixed within the tag itself to prevent shoplifters or other persons from removing or tampering with it. The tags are typically designed and manufactured such that access to the power supply is unavailable. Such removal or tampering would render the tag inoperable, thus defeating it as a security measure. Although in practice EAS tags are typically removed from an article upon purchase and subsequently stored for reuse on subsequent goods, a tag's ability to be reused may be undesirably limited by the life of the permanently affixed power supply. This limiting characteristic may thus result in the inability to effectively use a tag for a lengthy period of time, instead resulting in discarded tags replaced by tag with a fresh power supply, thereby increasing the overall cost of securing one's goods.
Some tag solutions include incorporating energy management hardware such as a wake-up switch in order to manage and limit the energy consumption. Typically, energy management hardware operates to limit tag power, performance and functionality in order to achieve long battery life. Such a result is undesirable.
Further, although one solution might be to include a very large power supply in the tag, such a solution is undesirable for a number of reasons. First, larger power supplies, e.g., batteries, add cost and weight to the tag as compared with smaller batteries. Second, a larger battery means a physically larger tag housing. Because the tags should be as unobtrusive as possible, affixing a physically large tag to an item can adversely impact the attractiveness of the protected item to the potential item purchaser. Also, as tag functionality increases, e.g., tags providing both EAS and radio frequency identification (“RFID”) functionality, the need to include additional components and circuitry inside the tag house also increases. As such, tag housing space resources are better used to provide the additional functionality as opposed to merely using the space for a large power supply.
It is therefore desirable to have a tag that can be repeatedly reused, despite the permanently affixed power supply, in a manner that does not necessitate a significant increase in tag size as compared with known tags.